HDAC4 or Histone Deacetylase 4 belongs to class II of the histone deacetylase/acuc/apha family and is a component of the histone deacetylase complex that represses transcription when tethered to a promoter. HDAC4 does not bind DNA directly, but through transcription factors MEF2C and MEF2D. Binding of the N terminus of HDAC4 to MEF2C represses MEF2C transcription activity. The catalytic domain of HDAC4 interacts with HDAC3 via the transcriptional corepressor NCOR2. Suppression of HDAC4 binding to NCOR2 and to HDAC3 results in loss of enzymatic activity associated with HDAC4.